A utilities provider approached Sensor Solutions to provide an instrumentation solution to enable the structural monitoring of a remote, existing High Pressure Pipeline in an area at high risk of land slip due to the steep gradient/topography of the site in the UK.
Sensor Solutions undertook a comprehensive site survey with the client and the various instrumentation options were presented. A solution was agreed and contract to supply a bespoke solution was signed.
This solution involved the excavation of the pipeline at various intervals along the length of the steep embankment to enable the installation of 18 Arc Welded Vibrating Wire Strain Gauges. These sensors were used to measure the strain in the pipeline resulting from ground movement. These sensors were selected as they have the advantage of being accurate, repeatable readings over long cable lengths, a long working life, offer long term stability and are both robust and reliable. The sensor cables were routed through 100m of underground conduit to an instrumentation point located adjacent to the site boundary fence where a battery powered data acquisition system was located.
The acquisition system was configured in a cabinet mounted on a support post. The DAQ system was battery powered due to the remote location and this was kept charged with a solar panel mounted on the support post above the cabinet. The data acquisition system required the use of 2 multiplexers to accommodate the number of vibrating wire strain gauges. The DAQ was wired to a modem and was configured to send data packets to a specific IP address using a data SIM. The data packets consisted of strain and temperature data together with a time and date stamp which was transmitted to an engineering support team tasked with asset management for the Utility company in an EU location at daily intervals. This enabled daily structural monitoring of the pipeline. Real time structural monitoring was an option with this DAQ but considered overkill for the clients needs so daily data packets were considered adequate for their monitoring needs.
The instrumentation was ringed with a protective fence and the pipeline will be actively monitored for years to come.
The Vibrating Wire Arc Weldable Strain Gauge measure strain in steel and cast iron members on buildings, bridges, dams and pipelines, as well as on reinforcing bars within mass concrete or piles. It can measure both tension and compression. Typical applications include:
- Monitoring strain and load during construction and service life
- Steel members and struts
- Monitoring of strain due to load
- Bridges and dams
- Structural Piles and mass concrete
- Monitoring strain in reinforcing bars during construction, pile testing and service life
